Dial fit system on the back, makes size adjustment super simple. ABS Tough Outer Shell. Airflow Optimised Venting. Stainless Steel Rivets. Fully Adjustable Straps for Optimum Fit With Easy Secure/Release Clip. Soft EPS Inner Foam Padding. Secure Padded Chin Strap For Comfort. Madd Gear Decals Front and Back. Low Profile and Light Weight Design. Certified Safety Standards. Extra Small / Small Size: 48 - 52 Small / Medium Size: 52 - 58 cm Medium / Large Size: 56 - 60 cm